IRRIGATION. 



IRRIGATION. 



earth, chiefly to produce increased crops of 

 grass, has been in use from a very early pe- 

 riod. In Oriental countries, in fact, the heat 

 of the climate is such, that in many situations 

 the now productive soil would be absolutely 

 sterile, were it not that the cultivator enriched 

 his ground <vith a copious supply of water. 

 The simile employed by Isaiah (i. 30), to indi- 

 cate barrenness and desolation, is " a garden 

 that hath no water." And that, in patriarchal 

 times, they laboured hard to supply their 

 grounds with water by means of various hy- 

 draulic machines, some of which resembled 

 the water-wheels of the fen districts of Eng- 

 land, and were worked by the feet of men, 

 something after the style of the modern tread- 

 mill, is certain. Moses alluded to this prac- 

 tice when he reminded the Israelites of their 

 sowing their corn in Egypt, and watering it 

 with their feet (Dent. xi. 10; 2 Kings, xix. 24), 

 and in the sandy soils of Arabia the same sys- 

 tem is still continued. (Niebuhr, vol. i. p. 121.) 

 According to Dr. Shaw, the following is the 

 modern mode of raising and using the water 

 of the Nile for the purpose of irrigation in 

 Egypt. "Such vegetable productions as re- 

 quire more moisture than what is occasioned 

 by the annual inundation of the Nile, are re- 

 freshed by water that is drawn at certain times 

 out of the river, and lodged in large cisterns 

 made for that purpose. The screw of Archi- 

 medes seems to have been the instrument for- 

 merly made use of for that purpose, though at 

 present the inhabitants either supply them- 

 selves with various kinds of leathern buckets, 

 or else with a sakiuh, as they call the Persian 

 wheel, which is the most useful and generally 

 employed machine. Engines and contrivances 

 of both these kinds are placed all along the 

 banks of the Nile, from the sea to the cataracts, 

 their situations being higher, and consequently 

 the difficulty of raising the water being greater, 

 as we advance up the river. When their pulse, 

 saffron, melon, sugar-canes, &c. (all of which 

 are commonly planted in rills), require to be 

 refreshed, they take out a plug from the bot- 

 tom of the cistern, and then the water gushing 

 out, is conducted from one rill to another by 

 the gardener, who is always ready as occasion 

 requires to stop and divert the current. In 

 Egypt at the present day, according to Dr. 

 Clarke, the water is sometimes raised for the 

 purposes of irrigation by means of a wicker 

 basket lined with leather, which is held by 

 cords between two men, who, by this laborious 

 means, swing it over the banks of the Nile into 

 the canal which conveys it to the lands intend- 

 ed to be irrigated. A machine similar to the 

 Persian wheel is still employed in China by 

 the cultivators for the purposes of irrigation. 

 This use of machinery for the purposes of 

 watering might, in fact, in many situations, be 

 advantageously employed in England to a 

 much greater extent than is commonly be- 

 lieved. It is well known how many thousand 

 acres of valuable land are profitably drained 

 by means of the steam-engine. At this very 

 period a public company is proposing to en- 

 close and drain an arm of the sea in Lincoln- 

 shire, by the assistance of its gigantic aid 

 Vet how rarely, if ever, is that power employed 



o irrigate the thirsty lands of England; lands 

 of all others the most profitable, the best adapt- 

 ed for the formation of water meadows. The 

 tracts to which I allude are those on a slope, 

 as on the side of a hill ; but these are rarely 

 found in situations where a sufficiently copious 

 supply of water can be constantly obtained for 

 the purposes of irrigation. Yet the quantity 

 thus required is act so large as to be beyond 

 the power of the steam-engine to supply ; thus, 

 to sufficiently saturate a square yard of a cal- 

 careous sand soil with water to the depth of 

 one foot, as in irrigation, requires about 30 

 gallons of water, equal to about 145,000 gal- 

 lons per imperial acre. Now, that the steam- 

 engine could readily and profitably supply this 

 quantity of water may be concluded from seve- 

 ral facts ; thus, the two engines, one of 80, the 

 other of 60 horses' power, which keep Deeping 

 Fen, near Spalding, completely drained, when 

 working, in 1835, only 96 days, of 12 hours 

 each, raised more than 14,000,000 tons of wa- 

 ter several feet. The district drained by them 

 contains about 25,000 acres (Brit. Farm. Mag. 

 N. S. vol. iii. p. 300), which would otherwise 

 be a complete swamp. And it has been proved 

 that, by a common condensing steam-engine, 

 one bushel of coals will raise more than 

 50,000,000 Ibs. of water one foot. In many 

 situations, therefore, where, for the purposes 

 of irrigation, good river water can be copious- 

 ly obtained, and fuel is at a moderate price, I 

 am confident that great results are yet to be 

 obtained by the aid of mechanical power. For, 

 by the steam-engine, the soils of all others the 

 best adapted for irrigation, may be successfully 

 brought into cultivation ; for instance, the poor 

 sands and gravels on the sloping banks of 

 many of the English and Scotish rivers, many 

 of whose waters, from being charged with or- 

 ganic matter, the carbonate and sulphate of 

 lime, and various earthy substances, are ex- 

 cellent for the use of water meadows. The 

 early employment of irrigation by the Egyp- 

 tians and Chinese was most likely the result 

 of the good effects which were observed to be 

 produced by the overflowings of the Nile and 

 the Chinese rivers ; for, in the " Celestial Em- 

 pire," irrigation has, it seems, been employed, 

 according to their veracious historians, for a 

 period long before that assigned to the flood. 

 In Italy, especially on the banks of the Po, the 

 cultivators of the earth have certainly employ- 

 ed this process for a period previous to the 

 days of Virgil (Georg. lib. i. v. 1069), 



Deinde satis fluvium inducit, rivosque sequentes 



and it is still carried on with a zeal and care 

 worthy of the art they practise. M. P. Cato, 

 the earliest of the Roman writers upon agri- 

 culture (150 years before Christ), in his ninth 

 chapter, told the Italian farmers to "make 

 water meadows, if you have water, and if you 

 have no water, have dry meadows." The di- 

 rections of Columella seem to have aU the 

 freshness of a modern age about them. He 

 was the first who noticed the inferior nu- 

 trition afforded by the hay from water mea- 

 dows. "Land," says he, "that is naturally 

 rich, and is in good heart, does not need to 

 have water set over it: and it is better hay 



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